Automatic firearm.



G. TOBORG. `1111101111110 PIREABM.

.APPLIUATION FILED FEB. 1, 1911.

Pam ad Nov. 14, 1911.

RBEEETS-BHEET 1.

G. TOBORG.

AUTOMATIC FIBEARM.

` y APPLICATION FILED TBB. 1, 1911. 1,008,498.

' Patent ed Nov. 14, 1911.

` SHEETS-SHEET 2.

GEORGE TOBORG, OF CHICAGO, ILLINOIS.

AUTOMATIC FIREARM.

Specification of Letters Patent. Paten bed NOV, 14: 1911 Application filed February 1, 1911.

Serial No. 605,886.

T o all whom it may concern.'

Be it known that I, GEORGE ToBonG, of

, with a recoil-operated, spring-pressed breechblock for passing the cartridges from the magazine up to the barrel for firing.

Other objects will appear from the deH scription of the mechanism and its mode of operation as presently given.

Said mechanism is illustrated in the accompanying drawings in which- Figure 1 is a side elevation of a gun containing my invention, looked at on the left side. Fig. 2 is an enlarged fragmentary view partly in elevation and partly in sectiont looked at on the right side. It shows a 22 rifle full size. Figs. 3 and 4 are detail cross sectional views taken on the respective lines 3 3 and 4 4 of Fig. 7 (Sheet 2). Fig. 5 is a fragmentary view in side elevation of the chamber-frame having the side plate removed and looked at on the left side. Fig. 6 is a' fragmentary longitudinal section through the frame and breech-block and showing the working parts below the breechblock in elevation and in the firing position Fig. 7 is an axial sectional view similar to that shown in Fig. 6 but represents the working parts in the reverse position. Fig.

8 is a detail showing a horizontal section onl the line 8 8 of Fig. 7. Fig. 9 is a'det-ail and shows a longitudinal section of the bottom plate of the frame with the trigger, sear, and hammer in elevation, looked at on the right side. Fig. 10 isa detail and shows a similar view to that of Fig. 9 without the hammer and sear, and the Sear-spring partly broken away. Fig. 11 is a detail and shows a fragment of the bottom plate of the frame in top plan view with the Sear-spring and trigger-spring broken away.

In the drawin sV 12 is thebarrel, 13 the chambered stockrame, 13 a detachable sideplate of the frame, 14 the cartridge magazine, 15 the breech-block, and 16 the cartridge lifter for' passing the cartridges from 1Ehe magazine up to tl .e level of the barrel ore. f

The breechblock 15 carries the firing-.pin 15a and is provided w th a bore in whichwa coiled spring 15hl is a 'ranged on a rod 15C which has a head thre .tded in the rear part of the frame. Said sp ling tends to hold the breech-block pressed :gainst the front end of the frame over the b Lrrel bore, and permit it to be thrown back ag `ainst the rear end.

The cartridge liftei 16 is pivoted at its rear, 16, to the frami and preferably provided with a spring 1( b which tends to bear downwardly. The he td or opposite end is thickened and cha-mbe 'ed to receive the cartridge from the mag azine when lowered. Fig. 8 shows a top view of the thickened head which is vertica ly divided longitudinally at the center znd'has the part 16c hinged to the part 1i as shown in dotted lines, a cartridge bein; shown in the chamber. A spring 16d mi unted on the part 16 (Fig. 7) is adapted to bear against the farther rear edge of p ,irt 16c so as to clamp the cartridge in the c iamber, through said part 16c slightly turI ing on its hinge pin 16E. The extreme fro it endof the lifter is provided with downw rrd extensions 16fand the front end of the f; ame is provided with an inwardly-projectii g wedge-shaped lug 16g which is adapted to'enter between the parts 16f and spread open the chamber to receive the cartridge from the magazine when the lifter is l eing lowered. Said downward extensions urther operate to pre vent cartridges fron coming out 'of the magazine when the ifter is raised to its limit. The location f the pivotal connection 16 of the lifter 16 relatively to the barrel bore, the form of the lifter, and its chamber end of the means employed to clamp the cartridge herein are such as to present the cartridge in level apposition to the barrel bore in -f `|ont Vof the retracted breech-block and witr its point free from contact with the barre l', asV seen'in Fig. 7.

The breech-block at the top fills the chamber of the frame an( normally covers the slot 13b for the ejecsion of the exploded shells. Centrally it b 1s a downward eXtension 15d which 1s rec ssed at 15, the-front end, to receive thel c .rtridge rim. It also has a longitudinal g1 )ove 15 (Fig. 4) for the part 16 of the lii ter to work 1n. Said downward extension passes through the chamber of the lifter-head when the latter is raised. The breech-block has the usual extractor llg and opposite thereto a projection 15h at the front end, and the interior Walls of the lifter-head chamber are provided with longitudinal grooves 16h for said extractor and projection to pass in. This means is adapted to hold the cartridge in line with the barrel bore during the passage of the breech-block cartridge into the barrel.

The cartridge chamber of the lifter is preferably made tapering from the rearl to the front to fit the taper of the cartridge, and the downward extension of the breechblock vis adapted to fill said chamber at the rear and spread open the parts 16 and 16c at the front against the action of the spring 16l on its passage forward so as to let the cartridge pass out. The said chamber is open at the top and the lines showing such opening at the surface preferably converge toward the forward end the same as do the interior walls of said chamber, and said chamber is contracted at the rear end just enough to stop the backward'movement of the cartridge properly in said chamber, but permit the forward movement of the breechblock through said chamber to shove the cartridge into the barrel.

At the rear o'f the lifter-head and just above the groove 16h (Figs. 4 and 7), the part 16 of the lifter is provided with a bevelpointed, spring bolt 16i which is adapted to engage the extractor 15g of the breech-block when the lifter is raised and the breech-block is thrown back, the bevel surface of said bolt on its upward movement striking the under side of the extractor and being thereby thrown back and caused to spring forward and engage over the top of said extractor. (Fig. 4.) This means is provided in order to prevent the lifter-head from falling below the line of the barrel bore and to guide the extractor and projection 15h of the breechblock into the grooves 161 of the lifter chamber. The walls of the lifter chamber are recessed at the front upper part (Fig. 8) so thataft-er the extractor. and projections 15h have passed thro-ugh said grooves 16h the lifter will be free to drop doWn when the breech-block is in its normal'position pressed against the forward end of the frame and covering the cartridge in the barrel.

The lifter has a rigid arm 16j at its rear ond which is extended upward across thev path of the breech-block and struck by the rear end ofthe breech-block vwhen thrown back bythe recoil of the firing. This overcomes the downward pressure ofthe spring 16-1 and causes the lifter-head t'o b eraised so as tobe caught and held up in line with the barrel by the engagementof spring bolt 1Gi with the extractor 15g. The spring of the Abreech-block in'nediately causes vthe return forward to shove theI of the latter to normal and shoves the cartridge into the barrel but the firing does not occur until the trigger is pulled. The hammer 17 swings on a pin 17iL mounted on the bottom plate of the chamber frame under the action of a main spring 17". It is thrown back into coclring position by the back action of the breech-block.

The sear 18 and trigger 19 are rabbeted together (Fig. .41) and pivoted on a pin 20 which is common to both but they have independent action. The trigger carries 'a spring locking bolt 19a which is bevelpointed and works in connection with a fixed cam 19b on the wall of the slot in which the trigger works. This bolt engages a projection 18a of the sear and locks the sear to the trigger, during a portion of the operation and releases it during another portion of the operation. Separate springs are provided, one 18h adapted to bear on a shoulder of the Sear and another 19C adapted to bear on a shoulder of the trigger, both bearing downwardly and tending to cause the scar to turn toward and bear against the hammer (Fig. 9). The action is that When the trigger is being pulled so as to lift the point of the sear out of its notch inthe hammer, the sear and trigger are locked and move together. trigger on theirpivot pin 2O causes the locking bolt to pass the cam 19b and spring out of engagement with the projection 18a so that the spring 18h will cause the Sear to turn back against the hammer independently of any further movement of the trigger. On release of the pulling on the trigger the spring 19c will cause the locking bolt to pass the cam 19b in the opposite direction and'be thereby set in locking engagement with the lug 18a of the sear as before.

This turn of the sea'r and For cooking the gun by hand, I have provided a slide 21 having a push-rod 21a adapted to pass through an opening in the front piece of the frame and abut against the front end of the breech-block. Said rod is not attached to the breech-block. The slide is attached to the barrel soas to be movable thereon. It is preferably adapted to fit over or upon the barrel and provided with inwardly-projecting pins adapted to travel in shallow grooves 12*1 formed in opposite sides of the barrel for a short distance at the breech end. B v taking hold of the slide and pulling it back the breech-block can'be pushed back by hand for introducing the first cartridge into the barrel or withdrawin a cartidge in order to unload the gun without firing it. The

slide is shoved forward by the first forward movement of the breech-block but is not otherwise affected by the action of the breech-block. y j

The numeral 22 Fig, `2 indicates the projecting end of a common turn key for locklng the barrel to the chamber frame in lieu of threading the parts together.

The ejector 23 (Fig. 8) stands out so as to strike the rim of the shell when pulled back b the extractor 15g and turn 1t out throug 1 the slot 13h in the ordinary way.

I am aware that prior to my invention automatic firearms have been made with the frame and chamber in combination with the reciprocating breech-block, the latter and its travel being only partially covered by the chamber, the breech-block being projected beyond the chamber at the rear in action. I therefore do. not claim such combination broadly, butthat I claim is:

1. In an automatic firearm, the combina tion with the barrel, magazine and chambered frame, of a cartridge lifter consisting of the part 16 pivoted at its rea-r end to the frame within the chamber and a hinged part 16c adapted to swing toward and from the part 16 at the front, the adjacent faces of said parts 16 and 16c beingrecessed to form a cartridge chamber, a spring 16(1 mounted on said part 16 and adapted to bear against the part y16, a downward extension at the front of the part 16C, and a camlikelug 16g on the front end of the frame, as specified.

2. In an automatic firearm, the combination with the barrel, magazine,and chambered frame, of a reciprocating, springressed breechblock, a cartridge lifter hav- 111g its rear end pivoted to the frame within its chamber and its front end having a cartridge holder and being vibratable across the path of the breech-block at the front, and locking means ada ted to connect the lifter and breech-block s idably together, as specified.

3. In an automatic firearm, the combination with the frame provided with the chamber, of the reciprocating breech-block provided with a longitudinal bore, the chamber being adapted to completely inclose the breech-block in its travel, a coil spring within said bore and projected therefrom againstthe rear artl` of the chamber tending to force the reech-block squarely against lthe front of the frame, a spring-pressed hammer adapted to be set by the backward movement of the breech-block, a vibratable cartridge klifter adapted to move transversely to the movement of the breech-block and to present the cartridge befoi e the retracted breech-block in level appositi on to the barrel bore, an angular uprightarn connected with the lifter and extended up in the chamber behind the breech-block anl near the end of its backward travel for im parting upward movement to the lifter, and a trigger for ieting and releasing the hammer, as speci-r 4t. In an automatic rear] A1, the combina tion with the barrel, cartridg 3 magazine, and chambered frame, of a vibr table cartridge lifter providedwith a grooi ed longitudinal cartridge chamber open at t 1e ends and, top and recessed at the front and above the grooves, and a reciprocatii tg breech-block provided with projections a1 tapted to travel through said grooves and iii ally to pass the recesses when the breech-bl ick is forward and the lifter is being lowe red, as and for the purposes specified.

5. In an automatic flrearl i, the combination with the chambered frz me, barrel, and magazine, of a horizontal] v-reciprocating, spring-pressed breech-block trranged in the upper part of the chamber, z nd a verticallyvibratable spring-pressed a rm 16 pivoted near to the rear of the fran te and carrying on its front end a cartridge l ifter adapted to receive a cartridge fom the n agazine, and an angular arm 16j extended ac foss the path of the breech-block near the re Lr of the chamber, as specified.

6. In an automatic firearl '1, the combination with the horizontal .yr-reciprocating breech-block of a spring-I: ressed hammer adapted to be set by the rec il action of the breech-block, a sear and trig ger mounted on a common shaft, and a spr: ng-locking bolt mounted on the trigger and adapted to engage and release the sear, as ind for thepurpose specified.

7. In an automatic firearfn, of the class described, the combination v ith the reciproeating breech-block, and th( spring-pressed ',hammer, of the trigger' am. sear provided with a spring locking bolt dapted tohold the sear and trigger 1n fixe f; relation while being pulled, and an indepei dent spring 18b for controlling the return ac 3ion of the Sear,

as specified.

GEORG E TOBORG. Vitnesses JOHN H. Romans, ADALYN PINKERToN.

Copies of this patent may be obtained for ve cents each, by addressing the Commi :sioner of Patents, Washington, D. C. 

